Configure Surface and Gesture MH3 Touch Project
Objective
This article provides information on creating a Touch Surface and Gesture project in Microchip's MPLAB® Harmony v3 platform as well as configuring surface and gesture parameters. The generated project supports the MPLAB XC32 compiler in MPLAB X IDE.
Procedure
Launch Touch Configurator
Follow steps one through eight in the Generate a Touch Project with MPLAB® Harmony page to launch the Touch Configurator in the MPLAB Harmony 3 platform.
Add Surface Sensors
Select the technology, click on the Surface Sensor, and configure it as per the sensor design.
Select Gesture Type from the drop-down menu. The available options are:
- No Gestures: 1 Touch Surface module is selected without the Gesture option.
- 1 Finger Gestures: 1 Touch Surface module is selected with the Gesture option.
- 1 & 2 Finger Gestures: 2 Touch Surface module is selected with the Gesture option.
Click Add.
It loads the Surface with the selected configuration and a warning will pop up asking you to enter the CPU and Peripheral default clock settings (Peripheral Touch Controller (PTC), Timer, Universal Asynchronous Receiver Transmitter (UART)).
- Click Yes to load CPU and Peripheral clock settings for optimized touch performance.
- Click No to configure CPU and Peripheral clocks manually.
Pin Selection
Click on the Pins tab.
Click on the PTC lines to re-assign the pins as per your design.
Parameters
Channel
Select the Parameters tab. Under Channel, Channel Parameters such as Filter Levels, Digital Gain, Analog Gain, Series Resistor, Charge Share Delay (CSD) (additional cycles), Prescaler, Threshold, Hysteresis, and Sensor Adjacent Key Suppression (AKS™) Group can be modified.
Sensor
Under Sensor, Sensor Parameters such as Detect Integration, Away from Touch Recal Integration Count, Away from Touch Recal Threshold, Touch Drift Rate, Away from Touch Drift Rate, Drift Hold Time, Re-burst mode and Max ON Duration can be modified.
Note: Touch response may be sluggish if Detect Integration is more than two for surface and gesture projects.
Scroll down in the same tab to change Scan Rate, Acquisition Frequency and Noise Handling using Frequency Hop.
Surface
Under Surface, Surface Parameters such as Position Resolution, Deadband Percentage, Median Filter, Infinite Impulse Response (IIR) Filter, Position Hysteresis, and Minimum Contact can be modified.
Note: When the gesture feature is enabled, position resolution should be less than or equal to 8-bit.
Gesture
Select the Gesture tab.
Note: All '1 Finger' or both '1 & 2 Finger' gestures are enabled based on the gesture selection during Surface Sensor creation.
To disable the Gestures after Surface Sensor creation, uncheck the ENABLE GESTURE check box.
The gesture parameters are shown below:
All the gesture time-related parameters are timed with a 10 ms timer, e.g. if Tap Release Timeout is configured as 5, this means 5 x 10 = 50 ms.
Note: While configuring Tap Release Timeout, Swipe Timeout, and Tap Hold Timeout follow the rule:
Tap Release Timeout < Swipe Timeout < Tap Hold Timeout.
Debug
To enable the DEBUG OPTION, click on Parameters from the panel on the left, then click on the Sensor tab from the list of tabs on top.
Two options are possible:
- Using 2D Touch Surface Utility
- Using Data Visualizer
Follow the steps given in the Guide to Connect to Microchip 2D Touch Surface Utility to visualize surface and gesture data using 2D Touch Surface Utility software.
Follow the steps given in Visualize Touch Data using Data Visualizer to visualize surface and button data using Data Visualizer software.
Summary
Select the Summary tab which displays the Project Configuration Summary and Touch Library Module Versions.
Generate Code
After Project Configuration, generate the code. The source and header files will be added to the project. Build the project and program the binary file to the device.
